Summer of Cicadas

While they may be noisy, cicadas are mostly harmless, and their emergence is a natural cycle that benefits the environment. Cicadas are common during summer, but a periodical cicada emerges from the underground every 13 and 17 years. Aren't we lucky? Cicadas don't bite or sting, and they aren't poisonous, so try to enjoy this natural phenomenon!

What is the cycle?

The cicadas then will mate and lay their eggs in tree branches; the female will make a slit in small branches of trees. The female then lays her eggs in these slits before dying. Around four to six weeks later, the eggs hatch, the young cicada nymphs fall to the ground, tunnel into the soil, and the cycle starts again.

Best Practices for your trees and plantings:

  • Avoid planting young trees less than 2 inches in diameter this spring. Because the cicadas lay eggs in slits in small tree branches, multiple cicadas laying eggs in a young tree could cause its rapid decline. The City is limiting its spring parkway planting this year and has deferred many planting locations until the fall.
  • Cover vulnerable small trees with netting.
  • Avoid contact insecticides. Due to the large scale of the emergence, insecticides can harm beneficial insects. The City will not apply systemic or contact insecticides during the emergence of the cicadas to decrease their activity.

Check out the video!
In this special video series, City Forester Corey Wierema shares more about cicadas and why they are such a special occurrence this year. 

Interactive Tree Map

Have you ever wondered what the largest tree is in Lake Forest? What is the most common tree? What type of tree do you drive by every day? Find answers to those questions on our interactive Tree Map! Use the Tree Map to pinpoint the species and size of over 30,000 trees found on City-owned property. Get started at

If you have any questions, please call the Forestry section at (847) 810-3564. 

Find more information on cicadas from the Lake County Forest Preserves.
Stay Informed!